list_sources

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations are provided, so the description carries the full behavioral burden, yet it only restates return content (chunk count and source list). It says nothing about ordering, completeness of the listing, size of the result set, or that the operation is a read-only enumeration.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

It is a single short sentence with no padding, but it is a sentence fragment that leads with output content rather than a verb and resource. Brevity here comes at the cost of a clear opening statement of action.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a zero-parameter read tool with an output schema already documenting return values, the bar is low and the description is just barely sufficient. It still fails to state the action or route the agent away from search_docs.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so there is no parameter semantics to explain; the baseline of 4 applies. The description does not misleadingly imply any inputs.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description names the resource (source documents) and mentions the chunk count, but it is a noun-phrase fragment with no verb, so it describes the return payload rather than stating the action. It also doesn't distinguish itself from the sibling search_docs, which an agent could easily confuse with a listing operation.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

There is no statement of when to use this tool versus search_docs, and no mention that it takes no filters. The agent must infer that this is a browse/enumerate operation and that search_docs is the filtered alternative.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.